I must be being particuarly dense today because I just don't understand where you are coming from with this!

Consider the following two variants of the code I posted:

Given:

__DATA__
Success

Invalid string!

...
    {
    if (/^[a-zA-Z0-9]{6,20}\z/) {
...

prints:

Invalid string: >Success
<
Invalid string: >
<
Invalid string: >Invalid string!
<

and

...
    {
    chomp;
    
    if (/^[a-zA-Z0-9]{6,20}\z/) {
...

prints:

Success: >Success<
Invalid string: ><
Invalid string: >Invalid string!<

[download]

Where is the problem? At the end of the day both variants tag the invalid strings invalid and the valid string valid. For the sample code the \z variant with no chomp prints the line end characters from the input data - but that was not important to the sample code, in fact it is distracting.

We have no information about why OP needs this code (although validating passwords does seem likely) and it's not clear to me what assumptions I am making that would cause a clever cracker to continue his career. Would you care to sketch a scenario showing how the solution is substandard?

DWIM is Perl's answer to Gödel

In reply to Re^5: how should i test whether a string contains between 6 and 20 letters and numbers by GrandFather
in thread how should i test whether a string contains between 6 and 20 letters and numbers by keiusui

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